Conventional techniques for recording and reproducing stereoscopic images include holography utilizing light coherence and a method that utilizes a plurality of images but not coherence. The latter is generally classified into two schemes; i.e., a binocular parallax type stereoscope scheme in which a two-dimensional image for the right eye and a two-dimensional image for the left eye are recorded, and the recorded images are reproduced such that an observer can see the image for the right eye through his right eye and the image for the left eye through his left eye; and a multi-view parallax type scheme utilizing images viewed from multiple points of view.
In holography, which is an ideal method of recording and reproducing three-dimensional stereoscopic images (hereinafter referred to as 3D images), data regarding the wave front of light emitted from an object are used in order to record stereoscopic image data. Wave front data are recorded in such a manner that scattered light from an object and separately provided reference light are caused to interfere with each other to thereby form interference fringes, and the thus-formed interference fringes are recorded. Therefore, an optical system and a recording medium to be used must have a spatial resolution close to the wavelength of light, and a coherent light source such as a laser must be used at least for recording. Since interference fringes depend on wavelength, handling of color images; i.e., recording of color images, requires three lasers, for the three primary colors, and a complex configuration.
[A] Typical examples of the binocular parallax type stereoscope scheme, which is one of the methods that does not utilize coherence, include stereoscopic movies to be observed by the use of polarization glasses, and stereoscopic televisions utilizing a lenticular sheet. However, in such stereoscopic movies and the stereoscopic televisions, although an image can be observed stereoscopically, a stereoscopic image is not reproduced completely. Thus, the image does not change even when the observer's position to see the image is shifted, and of course, the back side of the image cannot be seen. Therefore, the binocular parallax type stereoscope scheme provides pseudo-production of stereoscopic images.
[B] Typical examples of conventional techniques utilizing the multi-view type scheme include a multi-view parallax system in which the stereoscope is multi-view typed, and integral photography, in which multiple-lens images taken by the multiple-lens are reproduced in a reverse sequence.